The subject matter disclosed herein relates to casting preforms and methods of use thereof, and more particularly to casting preforms which provide targeted reinforcement to molded articles in order to improve certain physical properties, and methods of using the casting preforms.
Casting is a process for shaping a material, such as a ceramic, polymeric or metallic material, into a solid article when it is in fluid form. Casting provides an efficient and economical commercial manufacturing process for producing molded articles having desired or complex shapes. In the casting process, a liquid material is poured or introduced into a mold containing a hollow cavity of the desired shape where the liquid material solidifies upon cooling. The newly formed solid is termed a “casting.” Once solidified, the casting is ejected, broken out of, or otherwise removed from the mold, allowing for repetition of the molding process to produce multiple molded articles. Metal, ceramic, or plastic, are among the most common types of materials used in mold casting.
Molded articles are subjected to various physical stresses during their use or operation. The types of physical stresses that molded articles experience varies with the particular application in which they are used. For example, molded articles used as components in gas turbine engines which are subjected to high temperatures or rotary motion suffer from wear, fatigue, tensile and creep stresses. These physical stresses detrimentally affect the performance of the article, increase the need for maintenance and the frequency of routine service interval periods and decrease the overall lifetime of use of the article before the article is replaced. Such maintenance and replacement represent a substantial economic cost.
One approach to reinforcing molded articles produced via casting is the use of casting preforms. A casting preform, or insert, is a self-sustaining body which is incorporated into fluid casting material during the casting process, thereby forming a reinforced metal matrix. Casting preforms provide structural reinforcement and physical enhancements to the molded article.
Therefore, a need exists for casting preforms and methods of use thereof which provide targeted reinforcement to molded articles in order to increase certain physical properties, such as resistance to wear, high-temperatures, stresses, aggressive environments or a combination comprising at least one of the foregoing, thereby extending the period of time between service intervals or the lifetime of the component, or both.